Antimicrobial Effect of Pressurized Carbon Dioxide on <i>Listeria monocytogenes</i>

Abstract

ABSTRACT Listeria monocytogenes was inactivated by carbon dioxide at 35 and 45°C under pressures of 70.3 and 210.9 μg/cm 2 . Inactivation rates were sensitive to temperature and pressure. Other factors such as pH, moisture content, and environmental conditions of cell growth also influenced the effectiveness of CO 2 treatment. Bacteria were more difficult to inactivate when they were suspended in the medium with fat or oil, which may have protected the cells from penetration by CO 2 . Fat in growth medium where Listeria monocytogenes cells were inoculated apparantly increased their resistance. Several methods may be useful for increasing inactivation rates.